LOS ANGELES -- Investigators found what they believe are bloodstains on the sailboat belonging to missing former NBA player Bison Dele, and police in Tahiti suspect that he and two others were murdered by his older brother.

Authorities searching Dele's 55-foot catamaran at a Tahitian port found traces of what appeared to be blood inside and outside the boat, said Michel Marotte, Tahiti's chief prosecutor.

Marotte said the findings must be verified in a laboratory. "But it does seem to be blood traces," he told The Associated Press on Friday.

Meanwhile, Dele's brother, Miles Dabord, was in a coma and in critical condition at a hospital in Chula Vista, Calif. The FBI was waiting to question him after learning his identity only Thursday. Dabord was found unconscious in Mexico last week and taken to the hospital. He was arrested Thursday and charged with trying to steal his brother's identity.

Investigators believe Dele, who changed his name from Brian Williams in 1998, his girlfriend Serena Karlan and Bertrand Saldo, a French skipper sailing with the group, were killed July 6 or 7, after a layover in Tahiti, said Michel Marotte, chief prosecutor of Tahiti.

"We presume that the bodies of these people must be in the sea, the ocean, and will probably never be found," Marotte said. "But we're still looking."